Random insertion of injected DNA molecules into the macronuclear chromosome of Paramecium caudatum
نویسندگان
چکیده
positive transformant clones probed with the PcVenus sequence revealed that the injected DNA had become randomly inserted into the chromosome. Free linear monomers or multimers of injected DNA molecules as seen in P. primaurelia and P. tetraurelia were not evident even though the plasmid possessed extant telomeric repeats at its both extremities. We also cloned fragments containing the integration site of genomic DNA from transformant cells by plasmid rescue. Sequence analysis of the flanking DNA confirmed random insertion of the linear plasmid into the chromosomal DNA with extant telomere repeats at the fusion junction. Therefore, P. caudatum maintains introduced DNA in a unique manner by nonhomologous or illegitimate, rather than homologous recombination. Random insertion of injected DNA molecules into the macronuclear chromosome of Paramecium caudatum
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